JP5146665B2 - Electrophotographic toner and method for producing the electrophotographic toner - Google Patents

Description

  The present invention relates to an electrophotographic toner used in electrophotography. More particularly, the present invention relates to an electrophotographic toner having a relatively small particle size produced by a spraying method, having a stable productivity and a good fixing property, and a method for producing the electrophotographic toner.

In recent years, there has been a demand for higher image quality in the field of electrophotographic copying machines or printers. In order to satisfy this requirement, a reduction in the particle size of toner has been actively studied.
Conventionally, as a method for producing a toner, a pulverization method in which a binder resin, a colorant or the like is melt-kneaded, and the kneaded product is pulverized and classified is used. However, the toner obtained by this pulverization method has a wide particle size distribution of the toner particles, and there is a limit to the reduction in the particle size of the toner from the technical viewpoint and productivity such as yield.

  Recently, a toner production method using a suspension polymerization method or an emulsion polymerization aggregation method, so-called polymerization type toner, has been studied. In addition to this, a method called volumetric shrinkage called a polymer dissolution suspension method has been studied (see Patent Document 1). In this method, a toner material is dispersed and dissolved in a volatile solvent such as a low-boiling organic solvent, and this is emulsified and formed into droplets in an aqueous medium containing a dispersant, and then the volatile solvent is removed. Unlike the suspension polymerization method and emulsion polymerization aggregation method, this method is a versatile resin that can be used, and in particular, a polyester resin useful for a full color process that requires transparency and smoothness of the image area after fixing. It is excellent in that it can be used.

  However, since the above-described polymerization type toner is premised on the use of a dispersant in an aqueous medium, a dispersant that impairs the charging characteristics of the toner remains on the toner surface and the environmental stability is impaired. It is known that a defect occurs and a very large amount of washing water is required to remove this, and it is not always satisfactory as a manufacturing method.

  As an alternative method for producing toner, a method has been proposed in which fine droplets are formed using a piezoelectric pulse and then dried and solidified to form a toner (see Patent Document 2). Furthermore, a method has also been proposed in which fine droplets are formed by utilizing thermal expansion in the nozzle, and this is dried and solidified to form a toner (see Patent Document 3). Furthermore, a method for performing the same processing using an acoustic lens has been proposed (see Patent Document 4).

However, in the toner produced by the spray granulation method, as shown in FIG. 28B, the solid dispersion in the liquid tends to gather inside the toner particles, and the surface is formed with a component layer dissolved in the liquid. Has been. For this reason, there is a problem that the release agent dispersed in the toner composition liquid is also concentrated inside, and appropriate hot offset resistance cannot be obtained.
In the case of the spray granulation method, the larger the particle size of the insoluble dispersible component contained in the coating liquid, the more likely the head clogging occurs, and it is difficult to ensure production stability and quality stability. (Patent Document 5)

JP-A-7-152202 JP 2003-262976 A JP 2003-280236 A Japanese Patent Laid-Open No. 2003-262977 Japanese Patent Application No. 2007-275315 (unpublished)

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to solve the above-described problems and achieve the following objects. That is, an object of the present invention is to provide an electrophotographic toner satisfying high image quality, fixing properties and high productivity, and a method for producing the electrophotographic toner.

As a result of intensive studies, the present inventors have found that the above problem can be solved by dispersing a release agent having a specific shape characteristic in a toner in a specific state, thereby completing the present invention.
That is, the present invention relates to the following electrophotographic toners (1) to (11), the electrophotographic image forming apparatus (12), and the process cartridge (13).

(1) A toner composition solution in which at least a resin, a release agent, and a colorant are dissolved or dispersed in an organic solvent is discharged from a plurality of nozzles to form droplets, which are solidified. In the toner for electrophotography, the resin is soluble in the organic solvent, and the release agent has a 90% short side diameter of 100 to 500 nm and an average aspect ratio of 7 to 30 in the toner. An electrophotographic toner characterized in that the length of the long side is dispersed in the state of particles having a particle size of ½ or more and less than 1 of the particle size of the toner.
(2) The electrophotographic toner as described in (1) above, wherein the release agent has a melting temperature of 50 to 100 ° C.
(3) The toner for electrophotography according to (1) or (2), wherein the content of the release agent in the toner is 3 to 20 wt%.
(4) The electrophotographic toner according to any one of (1) to (3), wherein the volume average particle diameter is 3.0 to 7.0 μm.
(5) The discharge is performed while vibrating the storage unit from a plurality of nozzles provided in the storage unit that stores the toner composition liquid, according to any one of (1) to (4), Toner for electrophotography.
(6) The electrophotographic toner according to (5), wherein the nozzle is a vibration chamber nozzle head.
(7) In the ejection, the toner composition liquid is periodically discharged from the nozzles of the thin film by vibrating a thin film having a plurality of nozzles provided in a storage portion for storing the toner composition liquid by mechanical vibration means. The toner for electrophotography according to any one of (1) to (4), wherein
(8) The electrophotographic toner according to (7), wherein the mechanical vibration means is vibration generation means formed in an annular shape around a region where the thin film nozzle is provided.
(9) The electrophotography according to (7), wherein the mechanical vibration means is a vibration means having a vibration surface parallel to the thin film, and the vibration surface longitudinally vibrates in a vertical direction. Toner.
(10) The electrophotographic toner according to (9), wherein the vibrating means is a horn-type vibrator.
(11) The electrophotographic toner according to any one of (7) to (10), wherein a vibration frequency of the mechanical vibration means is 20 kHz or more and less than 2.0 MHz.
(12) An electrophotographic image forming apparatus using the electrophotographic toner according to any one of (1) to (11).
(13) An electrophotographic process cartridge using the electrophotographic toner according to any one of (1) to (11).

According to the electrophotographic toner of the present invention, an electrophotographic toner satisfying high image quality, fixing properties, and high productivity can be provided.
Further, according to the method for producing an electrophotographic toner of the present invention, it is possible to provide a method for producing an electrophotographic toner that satisfies high image quality, fixability, and high productivity and can be monodispersed.
In addition, according to the electrophotographic image forming apparatus and the process cartridge of the present invention, it is possible to provide an electrophotographic image forming apparatus and a process cartridge that satisfy high image quality and fixability.

Hereinafter, the electrophotographic toner of the present invention and the method for producing the electrophotographic toner will be described in detail.
The components constituting the toner composition in the present invention include at least a resin, a release agent, and a colorant, and other components such as an external additive and a charge control agent as necessary.

In the present invention, the determination of whether the resin, the release agent, and other toner components are soluble or insoluble in an organic solvent is based on the following criteria.
Under the condition of 20 ° C., a resin, a release agent, and other toner components are added so that the solid content concentration becomes 1% with respect to the solvent used, and stirred for 1 hour. Further, the mixed solution is allowed to stand at 20 ° C. for 24 hours. Visual evaluation is performed on the mixed solution after being left. If insoluble matter is confirmed on the bottom of the container, it is judged as insoluble. Moreover, insoluble matter cannot be confirmed, but when the liquid is cloudy, the liquid is put in a transparent glass cell, and the haze of white light measured at an optical path length of 10 mm is 2.0 or less. When it was larger than 0.0, it was insoluble.

(resin)
Examples of the resin include at least a binder resin.
There is no restriction | limiting in particular as said binder resin, Although resin used normally can be selected suitably and can be used, it is preferable that the gel component insoluble in a solvent is less than 0.5%. If the gel component is contained, the spray nozzle is clogged and the production stability is impaired. Therefore, in the case of using a resin containing a gel component, the gel component is filtered and used in a filtration step after the resin is dissolved.

  Examples of the resin used in the present invention include vinyl polymers such as styrene monomers, acrylic monomers and methacrylic monomers, copolymers of these monomers or two or more types, polyesters Examples thereof include a polymer, a polyol resin, a phenol resin, a silicone resin, a polyurethane resin, a polyamide resin, a furan resin, an epoxy resin, a xylene resin, a terpene resin, a coumarone indene resin, a polycarbonate resin, and a petroleum resin.

  Examples of the styrene monomer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, and pn-. Amyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene , Styrene such as p-chlorostyrene, 3,4-dichlorostyrene, m-nitrostyrene, o-nitrostyrene, p-nitrostyrene, or derivatives thereof.

  Examples of the acrylic monomer include acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, n-dodecyl acrylate, and acrylic. Examples include 2-ethylhexyl acid, stearyl acrylate, 2-chloroethyl acrylate, acrylic acid such as phenyl acrylate, or esters thereof.

  Examples of the methacrylic monomer include methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, n-dodecyl methacrylate, and methacrylic acid. And methacrylic acid or esters thereof such as 2-ethylhexyl, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and the like.

  The following (1)-(18) is mentioned as an example of the other monomer which forms the said vinyl polymer or a copolymer. (1) Monoolefins such as ethylene, propylene, butylene and isobutylene; (2) Polyenes such as butadiene and isoprene; (3) Vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide and vinyl fluoride; (4) Vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate; (5) Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; (6) Vinyl methyl ketone, vinyl hexyl ketone and methyl. Vinyl ketones such as isopropenyl ketone; (7) N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone; (8), vinyl naphthalenes; (9) acrylonitrile, Such as methacrylonitrile, acrylamide, etc. (10) unsaturated dibasic acids such as maleic acid, citraconic acid, itaconic acid, alkenyl succinic acid, fumaric acid, mesaconic acid; (11) maleic anhydride, citraconic anhydride, Unsaturated dibasic acid anhydrides such as itaconic anhydride and alkenyl succinic anhydride; (12) maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid monobutyl ester, citraconic acid monomethyl ester, citraconic acid monoethyl ester Monoesters of unsaturated dibasic acids such as citraconic acid monobutyl ester, itaconic acid monomethyl ester, alkenyl succinic acid monomethyl ester, fumaric acid monomethyl ester, mesaconic acid monomethyl ester; (13) dimethylmaleic acid, dimethylfumaric acid (14) α, β-unsaturated acids such as crotonic acid and cinnamic acid; (15) α, β-unsaturated acid anhydrides such as crotonic acid anhydride and cinnamic anhydride; 16) Monomers having a carboxyl group such as anhydrides of the α, β-unsaturated acids and lower fatty acids, alkenylmalonic acid, alkenylglutaric acid, alkenyladipic acid, acid anhydrides and monoesters thereof; ) Acrylic acid or methacrylic acid hydroxyalkyl esters such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate; (18) 4- (1-hydroxy-1-methylbutyl) styrene, 4- (1 -Hydroxy-1-methylhexyl) monomers having a hydroxy group such as styrene.

In the electrophotographic toner of the present invention, the vinyl polymer or copolymer of the binder resin may have a crosslinked structure crosslinked with a crosslinking agent having two or more vinyl groups. Examples of the crosslinking agent used in this case include aromatic vinyl vinyl compounds such as divinylbenzene and divinylnaphthalene. Examples of diacrylate compounds linked by an alkyl chain include ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, and 1,6. And xanthdiol diacrylate, neopentyl glycol diacrylate, and those obtained by replacing acrylates of these compounds with methacrylate. Examples of diacrylate compounds linked by an alkyl chain containing an ether bond include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, and dipropylene. Examples include glycol diacrylate and those obtained by replacing acrylate of these compounds with methacrylate.
Other examples include diacrylate compounds and dimethacrylate compounds linked by a chain containing an aromatic group and an ether bond. Examples of polyester diacrylates include trade name MANDA (manufactured by Nippon Kayaku Co., Ltd.).

  Examples of the polyfunctional crosslinking agent include pentaerythritol triacrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, tetramethylol methane tetraacrylate, oligoester acrylate, and acrylates of the above compounds in place of methacrylate, triallyl cyanide. Examples include nurate and triallyl trimellitate.

  These cross-linking agents are preferably used in an amount of 0.01 to 10 parts by weight, preferably 0.03 to 5 parts by weight, based on 100 parts by weight of the other monomers forming the vinyl polymer or copolymer. More preferred. Among these crosslinkable monomers, diacrylates bonded to a toner resin by a bond chain containing one aromatic divinyl compound (especially divinylbenzene), one aromatic group and an ether bond from the viewpoint of fixability and offset resistance. Preferred examples include compounds. Among these, a combination of monomers that becomes a styrene copolymer or a styrene-acrylic copolymer is preferable.

  Examples of the polymerization initiator used in the production of the vinyl polymer or copolymer of the present invention include 2,2′-azobisisobutyronitrile, 2,2′-azobis (4-methoxy-2,4- Dimethylvaleronitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile), dimethyl-2,2′-azobisisobutyrate, 1 , 1′-azobis (1-cyclohexanecarbonitrile), 2- (carbamoylazo) -isobutyronitrile, 2,2′-azobis (2,4,4-trimethylpentane), 2-phenylazo-2 ′ , 4'-dimethyl-4'-methoxyvaleronitrile, 2,2'-azobis (2-methylpropane), methyl ethyl ketone peroxide, acetylacetone peroxide, cyclohexanone Ketone peroxides such as oxide, 2,2-bis (tert-butylperoxy) butane, tert-butyl hydroperoxide, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, di -Tert-butyl peroxide, tert-butyl cumyl peroxide, dicumyl peroxide, α- (tert-butylperoxy) isopropylbenzene, isobutyl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide, m-tolyl peroxide, di-isopropylperoxydicarbonate, di-2-ethylhexylperoxydicarbonate Di-n-propyl peroxydicarbonate, di-2-ethoxyethyl peroxycarbonate, di-ethoxyisopropyl peroxydicarbonate, di (3-methyl-3-methoxybutyl) peroxycarbonate, acetylcyclohexyl Sulfonyl peroxide, tert-butyl peroxyacetate, tert-butyl peroxyisobutyrate, tert-butyl peroxy-2-ethylhexarate, tert-butyl peroxylaurate, tert-butyl-oxybenzoate, tert- Butyl peroxyisopropyl carbonate, di-tert-butyl peroxyisophthalate, tert-butyl peroxyallyl carbonate, isoamyl peroxy-2-ethylhexanoate, di-tert-butyl Kisa Hydro terephthalate to Rupaokishi, tert- butylperoxy azelate, and the like.

  In the toner production method of the present invention, when the binder resin is a styrene-acrylic resin, the molecular weight distribution is measured by GPC, which is a component soluble in tetrahydrofuran (THF) as a resin component (THF soluble component). A resin having a peak in the region of 3,000 to 50,000 (in terms of number average molecular weight) is preferable in terms of jetting stability, offset property, and storage stability. Moreover, in the measurement using GPC of the THF-soluble component, a binder resin having a main peak in a molecular weight region of 5,000 to 30,000 is more preferable, and has a main peak in a region of 5,000 to 20,000. A binder resin is most preferred.

  When the binder resin is a vinyl polymer such as styrene-acrylic resin, the acid value is preferably 0.1 mgKOH / g to 100 mgKOH / g, and preferably 0.1 mgKOH / g to 70 mgKOH / g. More preferably, it is most preferably 0.1 mgKOH / g to 50 mgKOH / g.

The following are mentioned as a monomer which comprises a polyester-type polymer.
Examples of the divalent alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, or diol obtained by polymerizing cyclic ethers such as ethylene oxide and propylene oxide to bisphenol A, etc. Is mentioned.

  In order to crosslink the polyester resin, it is preferable to use a trivalent or higher alcohol together. Examples of the trihydric or higher polyhydric alcohol include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, such as dipentaerythritol, tripentaerythritol, 1,2,4- Butanetriol, 1,2,5-pentatriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxybenzene , Etc.

  Examples of the acid component that forms the polyester polymer include benzene dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid or anhydrides thereof, alkyldicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid, or Unsaturated dibasic acids such as anhydride, maleic acid, citraconic acid, itaconic acid, alkenyl succinic acid, fumaric acid, mesaconic acid, maleic anhydride, citraconic anhydride, itaconic anhydride, alkenyl succinic anhydride And unsaturated dibasic acid anhydrides. Examples of the trivalent or higher polyvalent carboxylic acid component include trimet acid, pyromet acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxy-2-methyl-2-methylenecarboxypropane, tetra (methylene Carboxy) methane, 1,2,7,8-octanetetracarboxylic acid, empol trimer acid, or anhydrides thereof, partial lower alkyl esters, and the like.

  When the binder resin is a polyester resin, the molecular weight distribution of the THF soluble component of the resin component has a peak in the region of a molecular weight of 3,000 to 50,000 in terms of toner fixability and offset resistance. Further, as the THF-soluble component, a binder resin in which a component having a molecular weight of 100,000 or less is 90 to 100% is preferable, and a binder resin having a peak in a molecular weight region of 5,000 to 20,000 is more preferable. preferable.

  When the binder resin is a polyester resin, the acid value is preferably 0.1 mgKOH / g to 100 mgKOH / g, more preferably 0.1 mgKOH / g to 70 mgKOH / g, and 0.1 mgKOH / g. Most preferably, it is g-50 mgKOH / g.

  In the present invention, the molecular weight distribution of the binder resin is measured by gel permeation chromatography (GPC) using THF as a solvent.

  As the binder resin that can be used in the toner of the present invention, a resin containing a monomer component capable of reacting with both of these resin components in at least one of the vinyl polymer component and the polyester resin component can also be used. . Examples of monomers that can react with the vinyl polymer among the monomers constituting the polyester resin component include unsaturated dicarboxylic acids such as phthalic acid, maleic acid, citraconic acid, and itaconic acid, or anhydrides thereof. Examples of the monomer constituting the vinyl polymer component include those having a carboxyl group or a hydroxy group, and acrylic acid or methacrylic acid esters.

  Moreover, when using together a polyester polymer, a vinyl polymer, and another binder resin, what has 60 mass% or more of resin whose acid value of the whole binder resin has 0.1-50 mgKOH / g is preferable.

In the present invention, the acid value of the binder resin component of the toner composition is determined by the following methods (I) to (IV), and the basic operation conforms to JIS K-0070.
(I) The sample is used by removing additives other than the binder resin (polymer component) in advance, or the acid value and content of components other than the binder resin and the crosslinked binder resin are obtained in advance. . The sample pulverized product 0.5 to 2.0 g is precisely weighed, and the weight of the polymer component is defined as Wg. For example, when measuring the acid value of the binder resin from the toner, the acid value and content of the colorant or magnetic material are separately measured, and the acid value of the binder resin is obtained by calculation.
(II) A sample is put into a 300 (ml) beaker, and a mixed solution 150 (ml) of toluene / ethanol (volume ratio 4/1) is added and dissolved.
(III) Titrate with a potentiometric titrator using an ethanol solution of 0.1 mol / l KOH.
(IV) The amount of use of the KOH solution at this time is S (ml), a blank is measured at the same time, and the amount of use of the KOH solution at this time is B (ml), which is calculated by the following formula (1). However, f is a factor of KOH.
Acid value (mgKOH / g) = [(SB) × f × 5.61] / W (1)

  The toner binder resin and the composition containing the binder resin preferably have a glass transition temperature (Tg) of 35 to 80 ° C., more preferably 40 to 75 ° C., from the viewpoint of toner storage stability. If the Tg is lower than 35 ° C., the toner is likely to deteriorate in a high temperature atmosphere, and offset may easily occur during fixing. On the other hand, when Tg exceeds 80 ° C., fixability may be deteriorated.

(Coloring agent)
The colorant is not particularly limited and may be appropriately selected from commonly used resins. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent Yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Fu Issey Red, Parachlor Ortho Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmin Min BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Risor Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil Red, Nacridone Red, Pyrazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo, Ultramarine, Bitumen, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide , Pyridian, emerald green, pigment green B, naphthol green B, green gold, acid green , Malachite green lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof.
The content of the colorant is preferably 1 to 15% by mass and more preferably 3 to 10% by mass with respect to the toner.

  The dispersion of the colorant used in the present invention includes, but is not limited to, a method of mixing and kneading at least a resin and a colorant with a high shear force, a method of dispersing the dispersant / colorant in a solvent in advance, and the like. It is not something that can be done. For mixing and kneading, a high shearing dispersion device such as a three-roll mill is preferably used. Further, a bead mill is preferably used as an apparatus for dispersing in a solvent.

  The particle size of the colorant in the dispersion after dispersing the colorant is desirably 500 nm or less. If it is larger than 500 nm, the discharge nozzle is likely to be clogged. Further, when the toner is formed, the particle size of the colorant is increased, and the image quality is likely to be deteriorated. In particular, the OHP light transmittance is likely to be decreased. More preferably, it is 300 nm or less. Below 300 nm, the light transmission is remarkably improved and the color reproduction range is greatly improved. The particle size of the colorant can be determined with a laser diffraction / scattering particle size distribution measuring device “LA-920” (manufactured by Horiba, Ltd.).

  As the binder resin used at the time of dispersion, in addition to the polyester resin, for example, a polymer of styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene or the like; a styrene-p-chlorostyrene copolymer, styrene- Propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene- Octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer Polymer, styrene-vinyl Styrene copolymers such as tilketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer Combined; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane A polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin Aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, and the like. These may be used individually by 1 type, and 2 or more types may be mixed and used for them.

(Release agent)
The release agent used in the present invention is insoluble in a solvent that dissolves the resin, and is incompatible with the resin. In this case, the melting temperature of the release agent is preferably 100 ° C. or lower, more preferably 80 ° C. or lower. If the melting temperature exceeds 100 ° C., a cold offset tends to occur during fixing.

Moreover, as a melt viscosity of the said mold release agent, it is preferable that the measured value in the temperature 20 degreeC higher than the melting temperature of the said mold release agent is 5-1000 cps, and it is more preferable that it is 10-100 cps.
If the melt viscosity is less than 5 cps, the releasability may be lowered, and if it exceeds 1,000 cps, the effect of improving hot offset resistance and low-temperature fixability may not be obtained.
The content of the release agent in the toner is preferably 3 to 20 wt%. If it is less than 3 wt%, the release function is not sufficient, and if it exceeds 20 wt%, bleeding tends to occur, and problems are likely to occur in the development / transfer process. Preferably it is 5 to 10%.

Examples of mold release agents include plant waxes such as carnauba wax, cotton wax, wood wax, and rice wax; animal waxes such as beeswax and lanolin; mineral waxes such as ozokerite and cercin; paraffin, microcrystalline, and petrolatum Natural waxes such as petroleum waxes; In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax, polyethylene wax, and maleic acid-modified paraffin wax; synthetic waxes such as esters, ketones, and ethers; Furthermore, fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalic anhydride imide, chlorinated hydrocarbons; poly-n-stearyl methacrylate, poly-n-lauryl which are low molecular weight crystalline polymer resins A homopolymer or copolymer of a polyacrylate such as methacrylate (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.); a crystalline polymer having a long alkyl group in the side chain, or the like may be used.
These may be used alone or in combination of two or more.

  Furthermore, fatty acid esters, esters of aromatic acids such as phthalic acid, phosphoric esters, maleic esters, fumaric esters, itaconic esters, other esters, ketones such as benzyl, benzoin compounds, benzoyl compounds, hindered phenol compounds, benzo Examples include triazole compounds, aromatic sulfonamide compounds, aliphatic amide compounds, long chain alcohols, long chain dialcohols, long chain carboxylic acids, long chain dicarboxylic acids, and the like.

  Specifically, dimethyl fumarate, monoethyl fumarate, monobutyl fumarate, monomethyl itaconate, monobutyl itaconate, diphenyl adipate, dibenzyl terephthalate, dibenzyl isophthalate, benzyl, benzoin isopropyl ether, 4-benzoylbiphenyl , 4-benzoyldiphenyl ether, 2-benzoylnaphthalene, dibenzoylmethane, 4-biphenylcarboxylic acid, stearyl stearamide, oleyl stearamide, stearoleoleamide, octadecanol, n-octyl alcohol, tetracosanoic acid, eicosane Acid, stearic acid, laurin, nonadecanoic acid, palmitic acid hydroxyoctanoic acid, docosanoic acid, described in JP-A-2002-105414 Compounds of general formula (1) to (17), and the like.

These release agents may exhibit the following functions depending on the combination with the resin.
When the resin used and the release agent are compatible at a temperature equal to or higher than the melting temperature of the release agent, the release agent functions as a plasticizer. That is, the release agent improves the softening speed of the resin and has low-temperature fixability. In this case, the melting temperature of the release agent is preferably 120 ° C. or lower, more preferably 80 ° C. or lower. When the melting temperature exceeds 120 ° C., the effect on low-temperature fixability is lost.

In the present invention, the judgment as to whether the release agent is soluble (compatible) or insoluble (incompatible) in the resin is based on the following criteria.
5 parts by weight of a release agent is added to 95 parts by weight of a resin having a residual solvent of less than 200 ppm, and the glass transition point of a mixture well mixed in a mortar is measured under the following conditions.
The glass transition point of the mixture when the temperature is raised from 20 ° C. at 5 ° C./min is defined as Tg1.
The temperature is raised to 150 ° C. as it is, the temperature is lowered to 20 ° C. at 10 / min, and the glass transition point of the mixture when the temperature is raised again to 150 ° C. is defined as Tg2.
When Tg1-Tg2> 10 ° C., the release agent and the resin are compatible, and when Tg1-Tg2 <8 ° C., they are incompatible.

The release agent used in the present invention is dispersed in a state of particles having a 90% short side diameter of 100 nm to 500 nm and an aspect ratio of 7.0 to 30 in the organic solvent in the toner composition-containing liquid. . This dispersed state is similarly maintained in the toner after the toner composition-containing liquid is spray-dried. In the present invention, it is indirectly specified that the dispersed state in the toner, that is, the state in which the 90% diameter of the short side is dispersed in the state of particles of 100 nm or more and 500 nm or less and the aspect ratio is 7.0 or more and 30 or less. It defines the dispersion state in the organic solvent.
In the toner, the release agent is dispersed in the form of particles whose long side is 1/2 or more and less than 1 of the toner particle size.
When the 90% diameter of the short side exceeds 500 nm, nozzle clogging tends to occur and stable production becomes difficult.
On the other hand, if the 90% diameter of the short side is less than 100 nm, reaggregation is likely to occur and it is difficult to maintain a dispersed state.
If the long side is less than ½ of the toner particle size, the release agent is not likely to be located in the vicinity of the toner particle surface, and it is difficult for the release agent to ooze out of the toner at the time of fixing, resulting in an insufficient release function. On the other hand, if it is 1 or more, it is exposed on the surface of the toner particles, causing problems such as the influence on the toner charging characteristics due to bleeding and an increase in toner adhesion, resulting in a defective image such as background stains.
Further, when the long side satisfies the above conditions and the aspect ratio is less than 7, pulverization in the apparatus due to the decrease in particle strength, the amount of the release agent in the toner becomes excessive, and the cold offset property at the time of fixing decreases.

  The dispersed particle size of the dispersed release agent is determined by observing the dispersion with an electron microscope. The electron micrographs as shown in FIGS. 28C and 28D are binarized and processed and analyzed by image analysis software. At this time, in order not to treat the overlapping release agents with the same one, the observation sample is of course made as thin as possible, but the image of the overlapping portion is manually separated. .

(Organic solvent)
The organic solvent used in the present invention is an organic solvent in which the binder resin and the release agent can be dissolved, and is appropriately selected depending on the solubility of the resin and the release agent used.
Specific examples of the solvent used in the present invention include water; alcohols such as methanol, ethanol, isopropanol, n-butanol, and methyl isocarbinol; acetone, 2-butanone, ethyl amyl ketone, diacetone alcohol, isophorone, and cyclohexanone. Ketones such as N; N-dimethylformamide, amides such as N, N-dimethylacetamide; ethers such as diethyl ether, isopropyl ether, tetrahydrofuran, 1,4-dioxane, and 3,4-dihydro-2H-pyran Glycol ethers such as 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, ethylene glycol dimethyl ether; 2-methoxyethyl acetate, 2-ethoxyethyl acetate, 2-butoxyethyl Glycol ether acetates such as acetate; Esters such as methyl acetate, ethyl acetate, isobutyl acetate, amyl acetate, ethyl lactate, and ethylene carbonate; Aromatic hydrocarbons such as benzene, toluene, and xylene; Hexane, heptane, iso-octane Aliphatic hydrocarbons such as cyclohexane; halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, dichloropropane, chlorobenzene; sulfoxides such as dimethyl sulfoxide; N-methyl-2-pyrrolidone, N-octyl Examples include pyrrolidones such as -2-pyrrolidone. These solvents can be used alone or in admixture of two or more.

(Other materials)
As materials other than the resin release agent and the colorant, inorganic fine particles can be used as an external additive for imparting fluidity, developability, chargeability and the like to the toner particles.
The inorganic fine particles are not particularly limited and may be appropriately selected from known ones according to the purpose. For example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, titanate Strontium, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, carbonized Examples include silicon and silicon nitride. These may be used individually by 1 type and may use 2 or more types together.

The primary particle diameter of the inorganic fine particles is preferably 5 nm to 2 μm, and more preferably 5 nm to 500 nm. The specific surface area of the inorganic fine particles by BET method is preferably 20 to 500 m ² / g.
The content of the inorganic fine particles in the electrophotographic toner is preferably 0.01 to 5.0% by mass, and more preferably 0.01 to 2.0% by mass.

  The fluidity improver means a material that can be surface treated to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, a silane coupling agent, a silylating agent, Examples thereof include a silane coupling agent having an alkyl fluoride group, an organic titanate coupling agent, an aluminum coupling agent, silicone oil, and modified silicone oil. It is particularly preferable that the silica and the titanium oxide are surface-treated with such a fluidity improver and used as hydrophobic silica and hydrophobic titanium oxide.

  The cleaning improver is added to the toner in order to remove the developer after transfer remaining on the photoreceptor or the primary transfer medium, and includes, for example, fatty acid metal salts such as zinc stearate, calcium stearate, stearic acid, and the like. Examples thereof include polymer fine particles produced by soap-free emulsion polymerization such as methyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution, and those having a volume average particle size of 0.01 to 1 μm are suitable.

(Toner production method)
The method for producing an electrophotographic toner of the present invention comprises a storage unit storing a toner composition-containing liquid in which at least a resin, a release agent, and a colorant are dissolved or dispersed in an organic solvent. A discharge step of discharging the toner composition-containing liquid from the formed through-hole, a droplet forming step of dropping the toner composition-containing liquid discharged in the discharge step from a columnar shape through a constricted state, and the liquid A drying and solidifying step of drying and solidifying the droplets is sequentially provided.
Furthermore, it has a decreasing rate drying process, a classification process, and a mixing process after a drying solidification process as needed.

  The apparatus used in the method for producing an electrophotographic toner of the present invention is not particularly limited as long as it is an apparatus capable of producing an electrophotographic toner by a spray drying production method, and can be appropriately selected and used. A droplet forming means for discharging a liquid containing a toner composition containing at least a resin, a release agent, and a colorant to form droplets, a constant rate drying means for drying the droplets, and a residual solvent value. A toner manufacturing apparatus having a decreasing rate drying means capable of being used as a toner of 200 ppm or less and a mixing means for mixing with an external additive, wherein the residual solvent value of the spray dried product after the constant rate drying means is An external additive having a volume average particle diameter of 50 nm or more is mixed in a state of 10,000 ppm or more, and is reduced to less than 200 ppm through a reduction rate drying means.

(Droplet forming means)
As the droplet forming means, specifically, conventionally, a one-fluid nozzle (pressurizing nozzle) that pressurizes liquid and sprays from the nozzle, a multi-fluid spray nozzle that mixes and sprays liquid and compressed gas, a rotating disk Rotating disk sprayers that use liquids to form liquid droplets by centrifugal force are known, and these can be used, but it is difficult to obtain a toner having a small particle diameter, and the obtained toner Has a disadvantage that yield is lowered and productivity is lowered.
As a manufacturing method for obtaining a toner having a uniform particle size, the present inventors improved this drawback, and periodically ejected a toner composition liquid from a thin film having a plurality of uniform diameter nozzles by mechanical vibration means to form droplets. A periodic droplet formation method was found.

  In other words, in the production method of the present invention, the toner composition liquid droplets have a uniform particle size by mechanically vibrating a thin film having a plurality of nozzles to continuously discharge the toner composition liquid from the nozzles. Droplets can be generated. The mechanical vibration means may be arranged in any way as long as it vibrates in the direction perpendicular to the film having the nozzle. In the present invention, the following two systems are preferably used.

One is a method using mechanical means (mechanical longitudinal vibration means) having a vibration surface parallel to the thin film having a plurality of nozzles and longitudinally vibrating in the vertical direction. The mechanical vibration means (annular mechanical vibration means) formed in an annular shape is provided around the thin film having the nozzle.
Hereinafter, each method will be described.

(Mechanical longitudinal vibration means)
First, an example of a toner manufacturing apparatus provided with mechanical longitudinal vibration means will be described with reference to the schematic configuration diagram of FIG.
The toner manufacturing apparatus 1 includes a droplet ejecting unit 2 as droplet forming means for discharging a toner composition liquid containing at least a resin and a colorant into droplets, and the droplet ejecting unit 2 is disposed above. A particle forming unit 3 as a particle forming unit that solidifies the droplets of the toner composition liquid formed into droplets discharged from the droplet ejecting unit 2 to form toner particles T, and a toner formed by the particle forming unit 3 Toner collecting unit 4 that collects particles T, and toner particles T collected by toner collecting unit 4 are transferred through tube 5 and toner serving as toner storage means for storing transferred toner particles T is stored. A storage unit 6, a raw material storage unit 7 that stores the toner composition liquid 10, a pipe (liquid supply pipe) 8 that feeds the toner composition liquid 10 from the raw material storage unit 7 to the droplet ejection unit 2; Toner composition liquid 10 during operation And a pump 9 for feeding supply.

  In addition, the toner composition liquid 10 from the raw material container 7 is supplied to the droplet ejection unit 2 in a self-sufficient manner due to the droplet formation phenomenon by the droplet ejection unit 2. In particular, the pump 9 is used to supply the liquid. Here, as the toner composition liquid 10, here, a solution or dispersion liquid in which a toner composition containing at least a resin, a colorant, a crystalline compound soluble in an organic solvent or a crystalline compound composition is dissolved or dispersed in a solvent. Is used.

Next, the droplet ejecting unit 2 will be described with reference to FIGS.
FIG. 2 is a schematic cross-sectional explanatory view of the liquid droplet ejecting unit 2, and FIG. 3 is an explanatory bottom view of the main part when FIG. 2 is viewed from below.
The droplet ejection unit 2 includes a thin film 12 in which a plurality of nozzles (discharge ports) 11 are formed, mechanical vibration means (hereinafter referred to as “vibration means”) 13 that vibrates the thin film 12, and the thin film 12 and vibration means 13. And a flow path member 15 that forms a reservoir (liquid flow path) 14 for supplying a toner composition liquid 10 containing at least a resin and a colorant.

  The thin film 12 having the plurality of nozzles 11 is disposed in parallel to the vibration surface 13a of the vibration means 13, and a flow path is formed by a resin binder material in which a part of the thin film 12 does not dissolve in the solder or the toner composition liquid. It is bonded and fixed to the member 15 and has a substantially vertical positional relationship with the vibration direction of the vibration means 13. A communication means 24 is provided so that a voltage signal is applied to the upper and lower surfaces of the vibration generating means 21 of the vibration means 13, and the signal from the drive signal generating source 23 can be converted into mechanical vibration. As a communication means for providing an electrical signal, a lead wire whose surface is insulated is suitable. In addition, it is suitable for efficient and stable toner production that the vibration means 13 uses elements having a large vibration amplitude such as various horn type vibrators and bolted Langevin type vibrators described later.

  The vibration unit 13 includes a vibration generation unit 21 that generates vibrations and a vibration amplification unit 22 that amplifies the vibrations generated by the vibration generation unit 21. The drive unit (drive signal generation source) 23 drives a required frequency. When a voltage (drive signal) is applied between the electrodes 21 a and 21 b of the vibration generating means 21, vibration is excited in the vibration generating means 21, and this vibration is amplified by the vibration amplifying means 22 and arranged in parallel with the thin film 12. The vibrating surface 13a is periodically vibrated, and the thin film 12 is vibrated at a required frequency by the periodic pressure caused by the vibration of the vibrating surface 13a.

  The vibrating means 13 is not particularly limited as long as it can give a certain longitudinal vibration to the thin film 12 at a constant frequency, and can be appropriately selected and used, but the thin film 12 is vibrated. Therefore, the vibration generating means 21 is preferably a piezoelectric body 21A that is excited by a bimorph type flexural vibration. The piezoelectric body 21A has a function of converting electrical energy into mechanical energy. Specifically, by applying a voltage, flexural vibration is excited and the thin film 12 can be vibrated.

Examples of the piezoelectric body 21A constituting the vibration generating means 21 include piezoelectric ceramics such as lead zirconate titanate (PZT). However, since the amount of displacement is generally small, they are often used by being laminated. In addition, piezoelectric polymers such as polyvinylidene fluoride (PVDF), single crystals such as quartz, LiNbO ₃ , LiTaO ₃ , KNbO ₃ , and the like can be given.

The vibration means 13 may be arranged in any way as long as it gives vibration in the vertical direction to the thin film 12 having the nozzle 11, but the vibration surface 13 a and the thin film 12 are arranged in parallel.
In the illustrated example, a horn type vibrator is used as the vibration means 13 composed of the vibration generation means 21 and the vibration amplification means 22, and this horn type vibration amplifies the amplitude of the vibration generation means 21 such as a piezoelectric element. Since it can be amplified by the horn 22A as the means 22, the vibration generating means 21 itself for generating mechanical vibration may be a small vibration, and the mechanical load is reduced, leading to a long life as a production apparatus.

As the horn type vibrator, a known typical horn shape may be used, and examples thereof include a step type as shown in FIG. 4, an exponential type as shown in FIG. 5, a conical type as shown in FIG. Can do. In these horn-type vibrators, the piezoelectric body 21A is disposed on the surface of the horn 22A having a large area. The piezoelectric body 21A uses longitudinal vibration to induce efficient vibration of the horn 22A, and the horn 22A has a small area. The surface is a vibration surface 13a, and the vibration surface 13a is designed to be the maximum vibration surface. Lead wires 24 are arranged above and below the piezoelectric body 21, and an AC voltage signal is given from the drive circuit 23. The maximum vibration surface of these horn vibrators is designed to have a shape of 13a.
Further, as the vibration means 13, a particularly high-strength bolted Langevin type vibrator can be used. This bolted Langevin type vibrator is mechanically coupled with piezoelectric ceramics and will not be damaged during high amplitude excitation.

  The configuration of the reservoir, the mechanical vibration means, and the thin film will be described in detail with reference to the schematic diagram of FIG. The storage unit 14 is provided with at least one liquid supply tube 18, and as shown in a partial cross-sectional view, the liquid is introduced into the liquid storage unit through the flow path. Moreover, it is also possible to provide the bubble discharge tube 19 as needed. The droplet ejection unit 2 is installed and held on the top surface portion of the particle forming unit 3 by a support member (not shown) attached to the flow path member 15. In addition, although the example which has arrange | positioned the droplet injection unit 2 in the top | upper surface part of the particle formation part 3 is demonstrated here, the droplet injection unit 2 is provided in the drying part side wall used as the particle formation part 3, or a bottom part. It can also be set as the structure to install.

The size of the vibration means 13 that generates mechanical vibration is generally increased as the oscillation frequency decreases, and according to the necessary frequency, the vibration means is directly drilled to provide a reservoir. be able to. It is also possible to vibrate the entire storage part efficiently.
In this case, the vibration surface is defined as a surface on which the thin films having the plurality of nozzles are bonded.

  Different examples of the droplet jetting unit 2 having such a configuration will be described with reference to FIGS. The example shown in FIG. 7 uses a horn-type vibrator 80 composed of a piezoelectric body 81 as a vibration generating unit and a horn 82 as a vibration amplifying unit as the vibration unit 80 (13). A reservoir (flow path) 14 is formed. The droplet jetting unit 2 is preferably fixed to the wall surface of the particle forming unit 3 (drying means) by a fixing unit (flange unit) 83 integrally formed with the horn 82 of the horn-type vibrator 80. Loss of vibration From the viewpoint of preventing this, it may be fixed using an elastic body (not shown).

  The example shown in FIG. 8 is a bolt-clamped Langevin type vibrator configured by mechanically firmly fixing piezoelectric bodies 91A and 91B and horns 92A and 92B as vibration generating parts as bolts as vibration means 90 (13). 90 is used to form a reservoir (flow path 14) in the horn 92A. Depending on the frequency condition, the element may be large, and as shown in the drawing, the fluid introduction / discharge path and the reservoir can be processed in a part of the vibrator, and a metal thin film having a plurality of thin films can be attached.

  FIG. 1 shows an example in which only one droplet jetting unit 2 is attached to the particle forming unit 3, but a plurality of droplet jetting units 2 are arranged above the particle forming unit 3 (drying tower). Paralleling is preferable from the viewpoint of improving productivity, and the number thereof is preferably in the range of 100 to 1000 from the viewpoint of controllability. In this case, the toner composition liquid 10 is supplied to each storage section 14 of the droplet ejection unit 2 through the pipe 8 to the raw material storage section (common liquid reservoir) 7. The toner composition liquid 10 may be configured to be supplied in a self-contained manner as droplets are formed, or may be configured to supply the liquid supplementarily using the pump 9 during operation of the apparatus. it can.

Another example of the droplet ejecting unit will be described with reference to FIG. FIG. 9 is a schematic cross-sectional explanatory view of the liquid droplet ejecting unit.
In the droplet ejecting unit 2, similarly to the example described above, a horn-shaped vibrator is used with the vibrating means 13, and the flow path member 15 that surrounds the vibration generating means 13 and supplies the toner composition liquid 10 is disposed. The reservoir 14 is formed on the horn 22 of the vibration generating means 13 at the portion facing the thin film 12. Further, an air flow path forming member 36 that forms an air flow path 37 through which the air flow 35 flows is disposed around the flow path member 15 at a required interval. In order to simplify the drawing, only one nozzle 11 of the thin film 12 is shown, but a plurality of nozzles 11 are provided as described above.
As shown in FIG. 10, a plurality of, for example, 100 to 1,000 droplet ejection units 2 from the viewpoint of controllability are arranged side by side in the drying tower storage unit 3 </ b> A constituting the particle forming unit 3. Thereby, productivity can be further improved.

(Annular mechanical vibration means)
FIG. 11 shows the apparatus shown in FIG. 1 in which the droplet ejection unit is replaced with a ring type.
The ring type droplet ejecting unit 2 will be described with reference to FIGS. 12 is a cross-sectional explanatory view of the liquid droplet ejecting unit 2, FIG. 13 is a main surface bottom explanatory view of FIG. 12 viewed from the lower side, and FIG. 14 is a schematic cross-sectional explanatory view of droplet forming means.
The liquid droplet ejecting unit 2 includes a liquid droplet forming unit 11 that discharges the toner composition liquid 10 containing at least a resin and a colorant into liquid droplets, and a storage unit that supplies the liquid droplet forming unit 11 with the toner composition liquid 10. (Liquid flow path) 14 having a flow path member 15 formed thereon.

  The droplet forming means 16 includes a thin film 12 in which a plurality of nozzles (discharge ports) 11 are formed, and an annular vibration generating means (electromechanical conversion means) 17 that vibrates the thin film 12. Here, the thin film 12 is bonded and fixed to the flow path member 15 with a resin binding material that does not dissolve in the solder or the toner composition liquid at the outermost peripheral portion (region shown by hatching in FIG. 14). The vibration generating means 17 is arranged around the deformable area 16A (area not fixed to the flow path member 15) of the thin film 12. A drive voltage (drive signal) having a required frequency is applied to the vibration generating means 17 from a drive circuit (drive signal generation source) 23 through lead wires 21 and 22 to generate, for example, flexural vibration.

  The droplet forming means 16 is provided with an annular vibration generating means 17 around the deformable region 16A of the thin film 12 having the plurality of nozzles 11 facing the storage portion 14, for example, the comparison shown in FIG. Compared to the configuration in which the vibration generating means 17A holds the periphery of the thin film 12 as in the example configuration, the displacement amount of the thin film 12 is relatively large, and a relatively large area (φ1 mm or more) from which this large displacement amount can be obtained. ), A plurality of nozzles 11 can be arranged, and more droplets can be stably formed and discharged at a time than the plurality of nozzles 15.

  In FIG. 11, an example in which one droplet ejecting unit 2 is arranged is illustrated, but preferably, as shown in FIG. 16, a plurality of, for example, 100 to 1,000 (for example, from the viewpoint of controllability) In FIG. 16, only four droplet ejecting units 2 are arranged side by side on the top surface portion 3A of the particle forming unit 3, and each droplet ejecting unit 2 has a pipe 8A in the raw material storage unit 7 (common liquid reservoir). Then, the toner composition liquid 10 is supplied. As a result, more droplets can be discharged at a time, and the production efficiency can be improved.

(Droplet formation mechanism)
Next, the mechanism of droplet formation by the droplet ejecting unit 2 as the droplet forming means will be described.
As described above, the droplet ejecting unit 2 causes the thin film 12 having the plurality of nozzles 11 facing the storage unit 14 to propagate the vibration generated by the vibration means 13 that is a mechanical vibration means, thereby periodically causing the thin film 12 to move. By vibrating, a plurality of nozzles 11 are arranged in a relatively large area (φ1 mm or more), and droplets can be stably formed and discharged from the plurality of nozzles 11.

When the peripheral portion 12A of the simple circular film 12 as shown in FIG. 17 is fixed, the basic vibration has a node around the periphery, and as shown in FIG. 18, the cross section where the displacement ΔL is maximum (ΔLmax) at the center O of the thin film. It becomes a shape and vibrates up and down periodically in the vibration direction.
Further, it is known that higher order modes as shown in FIGS. 19 and 20 exist. These modes have one or more concentric nodes in a circular membrane, and are substantially axisymmetric deformation shapes. In addition, as shown in FIG. 21, the central portion has a convex shape 12c, so that the traveling direction of the droplet can be controlled and the vibration amplitude can be adjusted.

By the vibration of the circular thin film, the liquid near the nozzle provided in the circular films each place, the sound pressure P _ac proportional to the vibration speed Vm of the film occurs. It is known that the sound pressure is generated as a reaction of the radiation impedance Zr of the medium (toner composition liquid). The sound pressure is a product of the radiation impedance and the membrane vibration velocity Vm, and is expressed using the following equation (1). Is done.
P _ac (r, t) = Z _r · V _m (r, t) (1)
Since the vibration velocity Vm of the film varies periodically with time, it is a function of time (t), and various periodic variations such as a sine waveform and a rectangular waveform can be formed. Further, as described above, the vibration displacement in the vibration direction is different in each part of the film, and Vm is also a function of the position coordinates on the film. The vibration mode of the film used in the present invention is an axial object as described above. Therefore, it is substantially a function of the radius (r) coordinate.

As described above, a sound pressure proportional to the vibration displacement speed of the distributed film is generated, and the toner composition liquid is discharged into the gas phase in response to the periodic change of the sound pressure.
Since the toner composition liquid periodically discharged to the gas phase forms a sphere due to a difference in surface tension between the liquid phase and the gas phase, droplet formation occurs periodically.

As the vibration frequency of the film that enables droplet formation, a region of 20 kHz to 2.0 MHz is used, and a range of 50 kHz to 500 kHz is more preferably used. If the vibration period is 20 kHz or more, the dispersion of fine particles such as pigment and wax in the toner composition liquid is promoted by the excitation of the liquid.
Furthermore, when the displacement amount of the sound pressure is 10 kPa or more, the above-described fine particle dispersion promoting action is more preferably generated.

  Here, the diameter of the formed droplet tends to increase as the vibration displacement in the vicinity of the nozzle of the film increases. When the vibration displacement is small, a droplet is formed or does not become a droplet. In order to reduce such a variation in droplet size at each nozzle site, it is necessary to define the nozzle arrangement at an optimum position of the membrane vibration displacement.

In the present invention, as illustrated in FIGS. 18 to 20, the ratio R (= ΔL _max) of the maximum value ΔL _max and the minimum value ΔL _mim of the vibration direction displacement ΔL of the film near the nozzle generated by the mechanical vibration means. / ΔL _min ) is found to be able to keep the variation of the droplet size in a necessary region as toner fine particles capable of providing a high-quality image by disposing the nozzle at a site where 2.0 / _{min or} less. It was.
The conditions of the toner composition liquid were changed, and since the satellite generation start region was the same in the region of the viscosity of 20 mPa · s or less and the surface tension of 20 to 75 mN / m, the displacement amount of the sound pressure was 500 kPa or less. More preferably, it is 100 kPa or less.

(Other droplet formation methods)
As a manufacturing method for obtaining a toner having a uniform particle size, a solution or dispersion is quantitatively supplied to the storage unit, and a plurality of vibration units provided in the storage unit are vibrated by vibration means that contacts a part of the storage unit. Examples include means for discharging the raw material liquid from the through hole into the granulation space and forming the raw material fluid into droplets from a columnar shape through a constricted state.
Hereinafter, this method will be described with reference to FIGS.

  Since the storage section needs to be held at least in a state where the toner composition-containing liquid is pressurized, it is preferably made of a metal member such as SUS or aluminum and has a pressure resistance of about 10 MPa. However, it is not limited to this. Further, for example, as shown in FIG. 23, a structure provided with a mechanism 9 that is connected by a pipe 8 that supplies a liquid to the reservoir and holds a plate having a through hole is desirable. Moreover, the vibration means 2 which vibrates the whole storage part is in contact with the said storage part. The vibration means is connected to the vibration generator 10 and the conductive wire 11 and is preferably controlled. In order to stably form the liquid column, it is preferable to adjust the pressure in the reservoir and to provide the release valve 12 for removing bubbles inside.

It is preferable that the vibration means 2 excites the whole storage part having the through hole by one vibration means.
The vibrating means 2 for applying vibration to the storage unit 1 is not particularly limited as long as it can provide reliable vibration at a constant frequency, and can be appropriately selected and used. For example, it is preferable that the through hole is vibrated at a constant frequency by expansion and contraction of the piezoelectric body.

The piezoelectric body has a function of converting electrical energy into mechanical energy. Specifically, it is expanded and contracted by applying a voltage, and the through hole can be vibrated by the expansion and contraction.
Examples of the piezoelectric body include piezoelectric ceramics such as lead zirconate titanate (PZT). Generally, since the amount of displacement is small, the piezoelectric body is often used by being laminated. In addition, piezoelectric polymers such as polyvinylidene fluoride (PVDF), single crystals such as quartz, LiNbO ₃ , LiTaO ₃ , KNbO ₃ , and the like can be given.
The fixed frequency is not particularly limited and may be appropriately selected according to the purpose. However, 100 kHz to 10 MHz is preferable, and 200 kHz to 2 MHz is preferable from the viewpoint of generating micro droplets having a very uniform particle diameter. More preferred.

  The vibration means 2 is in contact with the storage portion, and the storage portion holds a plate having a through hole, and the vibration means and the plate having the through hole uniformly vibrate the liquid column generated from the through hole. From the viewpoint of giving, it is most preferable that they are arranged in parallel, and even if deformation occurs in the vibration process, it is desirable that the relationship be maintained within an inclination of 10 °.

  Even if only one through hole 4 is provided, particle production is possible. However, from the viewpoint of efficiently generating minute droplets having a very uniform particle diameter, a plurality of through holes 4 are provided and liquid discharged from each through hole is provided. The droplets are preferably dried with one solvent removal facility, in the example shown, the solvent removal facility 6.

  From the viewpoint of further improving productivity, it is more preferable to provide a plurality of reservoirs having the vibration means. At this time, the productivity of the toner particles is determined by the product of the number of droplets (frequency) generated per unit time, the number of vibration means, and the number of through-holes acting by one vibration means. From the viewpoint of operability, it is sufficient that the number of through-holes acted by one vibration means as much as possible, that is, the number of through-holes possessed by one reservoir is as large as possible. Not. Therefore, the number of through-holes associated with one reservoir that is vibrated by the one vibrating means is preferably 10 to 10,000 from the viewpoint of productivity and controllability. In order to more surely generate fine droplets having a very uniform particle size, it is more preferably 10 to 1,000.

  The support means 3 for fixing and supporting a part of the vibration means 2 is provided for fixing the storage section and the vibration means to the apparatus. The material is not particularly limited, but may be a rigid body such as metal. That's fine. If necessary, a rubber material, a resin material, or the like as a vibration reducing material may be provided in part so as not to disturb the vibration of the reservoir due to excessive resonance.

  As described above, the through-hole 4 that is a droplet forming unit is a member that discharges the toner composition raw material fluid as a liquid column. There is no restriction | limiting in particular as a material and shape of the said through-hole, Although it can be set as the shape selected suitably, For example, a discharge hole is formed with a metal plate with a thickness of 5-50 micrometers, and the opening diameter is 1. The fine liquid droplets having an extremely uniform particle size can be generated at a vibration frequency of 100 kHz or more without clogging the fine particle dispersion of 1 μm or less contained in the toner composition raw material fluid. From the viewpoint of achieving both. This is because the frequency region in which droplets can be stably obtained by the droplet formation phenomenon decreases substantially as the diameter of the through-hole increases, so that the vibration frequency of 100 kHz or more is considered in consideration of productivity. Is assumed. The opening diameter means a diameter if it is a perfect circle, and a minor diameter if it is an ellipse.

  The means 5 for supplying the liquid to the common liquid chamber is preferably a metering pump such as a tube pump, a gear pump, a rotary pump, or a syringe pump. Moreover, the pump of the type pressurized and sent with compressed air etc. may be used. With these liquid supply means, the common liquid chamber is filled with the toner composition raw material fluid, and the pressure can be increased to a pressure at which droplets can be formed. The liquid pressure can be measured with a pressure gauge attached to the pump or a dedicated pressure sensor.

(Thin film with multiple nozzles)
As described above, the thin film having the nozzle is a member in which a solution or dispersion of the toner material is discharged to form droplets.

The material of the thin film 12 and the shape of the nozzle 11 are not particularly limited and may be appropriately selected. For example, the thin film 12 is formed of a metal plate having a thickness of 5 to 500 μm and An opening diameter of 3 to 30 μm is preferable from the viewpoint of generating fine liquid droplets having a very uniform particle diameter when the liquid droplets of the toner composition liquid 10 are ejected from the nozzle 11. The opening diameter of the nozzle 11 means a diameter if it is a perfect circle, and a minor diameter if it is an ellipse.

(Drying means)
The toner composition-containing liquid thus formed into droplets is then made into toner particles by removing the solvent in a solvent removal facility. Since this solvent removal equipment is common to the droplets obtained by the above-described methods, this will be described with reference to FIG.
In the following, the terms “constant rate drying” and “decreasing rate drying” are used, but these terms will be described. Generally, when a material containing moisture is brought into contact with a drying gas and dried by heating, the moisture content decreases linearly after a constant rate drying period in which the moisture content W decreases linearly after the initial preheating period. It becomes a decreasing rate drying period that saturates without. In the case of toner droplets, the solvent is removed instead of removing the water, but the same phenomenon as described above also occurs when removing the solvent. Therefore, in this specification, the initial preheating period has elapsed. The desolvation phenomenon in which the water content decreases linearly is called constant rate drying, and the desolvation phenomenon in which the water content does not decrease linearly and saturates is called “decreasing drying”.

(Constant rate drying means)
The solvent removal equipment 3 which is a constant rate drying means is not particularly limited as long as the solvent of the droplet 31 can be removed, but an air flow is generated by flowing a dry gas 35 in the same direction as the droplet 13 flight direction. The droplet 31 is transported in the solvent removal equipment 6 by the air flow, and the solvent in the droplet 31 is removed during the transport to form spray-dried particles (toner particles) T. preferable. Here, “dry gas” means a gas having a dew point temperature of −10 ° C. or lower under atmospheric pressure. The dry gas is not particularly limited as long as it is a gas capable of drying the droplets 31, and examples thereof include air and nitrogen gas.

  The temperature of the drying gas is preferably higher in terms of drying efficiency, and even if a drying gas having a boiling point higher than the solvent used is used due to the characteristics of spray drying, the constant rate drying region during drying is used. Thus, the droplet temperature does not rise above the boiling point of the solvent, and the resulting toner is not thermally damaged. However, since the main constituent material of the toner is a thermoplastic resin, when it is exposed to a dry gas above the glass transition point of the resin used after drying, that is, in the reduced rate drying region, the toners are thermally fused. Or the shape becomes spherical. Therefore, it is desirable to optimize the temperature of the dry gas in combination with the air volume and the discharge liquid volume so that the product temperature after drying is less than 50 ° C.

  In the toner production apparatus of the present invention, the reduction rate drying means can be provided separately from the airflow drying means. As the rate-decreasing means, a conductive electrothermal stirrer, a fluidized bed dryer, a moving bed dryer or the like is used. The drying temperature at the time of reduced rate drying is preferably lower than the glass transition point of the resin to be used and the melting temperature point of the release agent, more preferably 10 ° C. or more.

(Toner collecting part)
The toner collecting unit 4 is a member provided at the bottom of the toner particle manufacturing apparatus from the viewpoint of efficiently collecting and transporting toner.
The structure of the toner collecting portion 4 is not particularly limited as long as the toner can be collected, and can be selected as appropriate. From the above viewpoint, as shown in the illustrated example, the tapered surface 41 whose opening diameter is gradually reduced. The toner particles T are formed from the outlet portion whose opening diameter is smaller than that of the inlet portion, the dry gas A is used to form the flow of the dry gas, and the toner particles are separated from the toner by the flow of the dry gas. It is preferably transferred to the storage container 6.
As the transfer method, as in the illustrated example, the toner particles T may be pumped to the toner storage container by a dry gas, or the toner particles T may be sucked from the toner storage container side.

Although there is no restriction | limiting in particular as a flow of the said dry gas, From a viewpoint which can generate the centrifugal force and can convey the toner particle T reliably, it is preferable that it is a vortex | eddy_current.
Further, from the viewpoint of more efficiently transporting the toner particles T, it is more preferable that the toner collecting portion and the toner collecting container are formed of a conductive material and are connected to the ground. preferable. The toner manufacturing apparatus preferably has an exposure specification.

(Decrease rate drying and external additive mixing means)
In the toner manufacturing method of the present invention, the reduction rate drying means is provided separately from the constant rate drying means. If the spray particle temperature in the constant rate drying step is less than the glass transition point of the resin that uses the constant rate drying step, a solvent of 10,000 ppm or more remains in the spray particles after the constant rate drying step. It is very difficult to efficiently remove the remaining residual solvent.
Use of spray particles having such residual solvent value as toner causes problems such as odor and safety. Therefore, the residual solvent value needs to be less than 200 ppm. Preferably it is less than 50 ppm.

  As the rate-decreasing means, a conductive heat transfer type agitation dryer, fluidized bed dryer, moving bed dryer, or the like is used. Usually, the melting temperature point of the release agent substance of the spray-dried particles is equal to or higher than the glass transition point of the resin to be used. A temperature lower by 10 ° C. or more is more preferable. Moreover, in order to raise drying efficiency, it is preferable that it is a drying temperature more than normal temperature. More preferably, the glass transition point of the resin used is Tg−20 ° C. or higher.

The present invention is characterized in that an external additive having a volume average particle size of 50 nm or more is mixed in a state where the residual solvent value of the spray-dried product after the constant rate drying step is 10,000 ppm or more, and is reduced to less than 200 ppm through the reduction rate drying step. To do. By mixing external additives with spray particles with a residual solvent value of 10000 ppm or more, it becomes a spacer between spray particles to prevent particles from aggregating and binding, and the surface of the spray particles is exposed to a dry gas. Thus, the drying efficiency can be greatly improved.
At this time, the volume average particle size of the external additive must be 50 nm or more, and preferably 100 nm or more. Particles less than 50 nm are buried in spray particles immediately after mixing, and the spacer effect is lost immediately.

  As described above for (external additive), an external additive having a thickness of 50 nm or more imparts a spacer effect and improves developability and transferability. On the other hand, the external additive is easily separated from the toner particles, and the detached external additive forms an image. There is a problem that the film adheres to the photosensitive member or transfer member in the apparatus and causes filming. By mixing in a state where the toner particle residual solvent value is 10,000 ppm or more, the toner particle surface can be mixed in a slightly plasticized state, so that a part of the toner particle is embedded and the separation rate is greatly reduced. Because of the large particle size, the spacer effect can be maintained without being completely buried in the toner particles. Further, mixing at less than 10,000 ppm makes it difficult to suppress the separation rate.

  The external additive mixing step and the rate-decreasing drying step can be performed simultaneously by using, for example, the rate-decreasing drying of the conductive heat transfer stirring drying method. One example of such a device is a ribocorn manufactured by Okawara Seisakusho. By mixing the external additive and drying at a reduced rate in the same step, it becomes possible to obtain toner particles more efficiently.

The stripping method is effective for decreasing rate drying. The stripping method is a method of accelerating drying by exposing to water vapor as a means of removing the residual solvent, reducing the affinity between the resin and the solvent and utilizing the azeotropic phenomenon of the solvent and water. The granulation method used is a method generally used during drying. The residual solvent value is drastically reduced by removing the residual solvent by stripping and then drying with water.
As a result of the inventor's examination, it has been found that even when this stripping method is used, it is possible to increase the solvent removal efficiency by mixing after adding an external additive having a volume average particle diameter of 50 nm or more.
For the moisture drying in the stripping method, conduction heat transfer type stirring drying, fluidized bed drying, moving bed drying, or the like is used. Further efficient drying is possible by vacuum drying with conductive heat transfer type stirring and drying.

The electrophotographic toner uses an external additive having a volume average particle size of less than 30 nm depending on the purpose in order to impart fluidity and chargeability. It has been confirmed that such external additives are less likely to function when they are embedded in toner particles. Further, since the particle size is as small as less than 30 nm, the toner particles tend to be buried in the toner particles.
When mixed in a state where the toner particle residual solvent value is 10,000 ppm or more, the external additive is completely buried and the effect is not generated. Further, when the toner particles having a residual solvent value of less than 200 ppm are mixed, the toner particles are less likely to be buried and can be mixed in a state where they adhere to the toner particles.

(Other means)
The toner of the present invention is mixed with an external additive as necessary. It is possible to simultaneously perform the external additive mixing step and the reduction rate drying step. By simplifying the process, the process can be simplified.

(Function)
According to the toner particle manufacturing method of the present invention described in detail above, the number of droplets generated from one through hole is very large, tens of thousands to several million per second. It is hard to happen. For this reason, a very uniform droplet diameter can be obtained, and it can be said that it is the most suitable method for producing toner from the viewpoints of high efficiency, low cost and sufficient productivity that do not require a classification step.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.
FIG. 24 is a diagram illustrating an example of an internal configuration of a color image forming apparatus that is an example of an electrophotographic image forming apparatus. This specific example is a tandem indirect transfer type electrophotographic copying apparatus, but the image forming apparatus of the present invention is applicable to all electrophotographic systems using a two-component developer, and is limited to this specific example. Not a thing. In the figure, reference numeral 100 denotes a copying apparatus main body, 200 a paper feed table on which the copying apparatus main body 100 is mounted, 300 a scanner (reading optical system) mounted on the copying apparatus main body 100, and 400 an automatic document feeder (ADF) mounted thereon. ). An endless belt-like intermediate transfer member 10 extending in the lateral direction is provided at the center position of the copying apparatus main body 100. In the illustrated example, the intermediate transfer member is wound around three support rollers 14, 15, and 16 so as to be able to rotate and convey clockwise in the drawing. In this illustrated example, an intermediate transfer body cleaning device 17 that removes residual toner remaining on the intermediate transfer body 10 after image transfer is provided to the left of the second support roller 15 among the three support rollers. Further, among the three support rollers, the intermediate transfer member 10 stretched between the first support roller 14 and the second support roller 15 has black, yellow, magenta, and cyan along the transport direction. The tandem image forming unit 20 is configured by arranging the four image forming units 18 side by side. An exposure device 21 is further provided immediately above the tandem image forming unit 20 as shown in FIG.

  On the other hand, a secondary transfer device 22 is provided on the opposite side of the intermediate transfer body 10 from the tandem image forming unit 20. In the illustrated example, the secondary transfer device 22 is configured by spanning a secondary transfer belt 24, which is an endless belt, between two rollers 23, and is pressed against the third support roller 16 via the intermediate transfer body 10. The image on the intermediate transfer body 10 is transferred to a sheet. A fixing device 25 for fixing the transfer image on the sheet is provided beside the secondary transfer device 22. The fixing device 25 is configured by pressing a pressure roller 27 against a fixing belt 26 that is an endless belt. The secondary transfer device 22 described above also has a sheet transport function for transporting the image-transferred sheet to the fixing device 25. In the illustrated example, a sheet reversing device 28 for reversing the sheet so as to record images on both sides of the sheet is provided below the secondary transfer device 22 and the fixing device 25 in parallel with the tandem image forming unit 20 described above. Is provided.

  Now, when making a copy using this color electrophotographic apparatus, a document is set on the document table 30 of the automatic document feeder 400. Alternatively, the automatic document feeder 400 is opened, a document is set on the contact glass 32 of the scanner 300, and the automatic document feeder 400 is closed and pressed by it. When a start switch (not shown) is pressed, when a document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the other contact glass 32. Immediately, the scanner 300 is driven, and the first traveling body 33 and the second traveling body 34 travel. Then, the first traveling body 33 emits light from the light source and further reflects the reflected light from the document surface toward the second traveling body 34, and is reflected by the mirror of the second traveling body 34 and passes through the imaging lens 35. The document is placed in the reading sensor 36 and the original content is read. When a start switch (not shown) is pressed, one of the support rollers 14, 15 and 16 is rotationally driven by a drive motor (not shown), and the other two support rollers are driven to rotate, so that the intermediate transfer body 10 is moved. Rotate and convey. At the same time, the individual image forming means 18 rotates the photoconductor 40 to form black, yellow, magenta, and cyan monochrome images on each photoconductor 40. Then, along with the conveyance of the intermediate transfer member 10, the single color images are sequentially transferred to form a composite color image on the intermediate transfer member 10.

On the other hand, when a start switch (not shown) is pressed, one of the paper feed rollers 42 of the paper feed table 200 is selectively rotated, and the sheet is fed out from one of the paper feed cassettes 44 provided in multiple stages in the paper bank 43, thereby separating rollers 45. Then, the sheets are separated one by one into the paper feed path 46, transported by the transport roller 47, guided to the paper feed path 48 in the copying machine main body 100, and abutted against the registration roller 49 and stopped. Then, the registration roller 49 is rotated in synchronization with the composite color image on the intermediate transfer member 10, the sheet is fed between the intermediate transfer member 10 and the secondary transfer device 2, and transferred by the secondary transfer device 22. A color image is recorded on the sheet. The image-transferred sheet is conveyed by the secondary transfer device 22 and sent to the fixing device 25. The fixing device 25 applies heat and pressure to fix the transferred image. Are discharged and stacked on the discharge tray 57. Alternatively, it is switched by the switching claw 55 and put into the sheet reversing device 28, where it is reversed and guided again to the transfer position, and an image is recorded also on the back surface, and then discharged onto the discharge tray 57 by the discharge roller 56. On the other hand, the intermediate transfer body 10 after the image transfer is removed by the intermediate transfer body cleaning device 17 to remove residual toner remaining on the intermediate transfer body 10 after the image transfer, so that the tandem image forming unit 20 can prepare for another image formation.

  In the tandem image forming unit 20 described above, each image forming unit 18 includes a charging device 60, a developing device 61, a primary transfer device 62, and the like around the drum-shaped photoconductor 40. The photoconductor cleaning device 63 has at least a blade cleaning member. Further, as shown in FIG. 25, the developing device 61 includes a toner supply side stirring screw 66, a developer carrier side stirring screw 67, a developer carrier (developing roller) as a developer stirring / conveying means in a developer container 65. 68) A doctor blade 77 is provided. A supply port (not shown) is provided on the outer wall of the container of the first developer stirring chamber 86, and toner is supplied from a toner supply device (not shown). The agitation screw 66 on the toner replenishment side agitates and conveys the toner replenished from the toner replenishing device and the developer (two-component developer having magnetic particles and toner) in the developer container 65. Further, the stirring screw 67 in the second developer stirring chamber 87 (on the developer carrying member side) stirs and conveys the developer in the developer container 65. (Hereinafter, the second developer stirring chamber is referred to as a development side stirring chamber.) The replenishment side stirring chamber and the development side stirring chamber are partitioned by a partition plate 80 as shown in FIG. There is a passing opening. The developer in the developing side agitating chamber is pumped up by the developing sleeve, and the amount thereof is regulated by a doctor blade and supplied to the rubbing portion with the photosensitive member as a latent image carrier. At this time, the developer is given the greatest rubbing force by the doctor blade.

  FIG. 27 shows a schematic configuration of the process cartridge. In FIG. 27, 210 indicates the entire process cartridge, 211 is a photosensitive member, 212 is a charging unit, 213 is a developing unit, and 214 is a cleaning unit.

  In the present invention, a plurality of components such as the photosensitive member 211, the charging device unit 212, the developing unit 213, and the cleaning unit 214 described above are integrally combined as a process cartridge, and the process cartridge is copied. It is configured to be detachable from an image forming apparatus main body such as a printer or a printer.

  In the image forming apparatus having the process cartridge containing the toner of the present invention, the photosensitive member is rotationally driven at a predetermined peripheral speed. In the rotation process, the photoreceptor is uniformly charged with a positive or negative predetermined potential on its peripheral surface by the charging means, and then receives image exposure light from image exposure means such as slit exposure or laser beam scanning exposure. In this way, an electrostatic latent image is sequentially formed on the peripheral surface of the photosensitive member, and the formed electrostatic latent image is developed with toner by the developing unit, and the developed toner image is transferred from the sheet feeding unit to the photosensitive member and the transferring unit. In the meantime, the image is sequentially transferred to a transfer material fed in synchronization with the rotation of the photosensitive member. The transfer material that has received the image transfer is separated from the surface of the photosensitive member, introduced into the image fixing means, and fixed on the image, and printed out as a copy (copy). The surface of the photoconductor after the image transfer is cleaned by at least removing the residual toner by a cleaning unit having a blade cleaning member, and after being further neutralized, it is repeatedly used for image formation.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to a following example at all.
(Preparation of colorant dispersion)
First, a carbon black dispersion as a colorant was prepared.
Carbon black (Regal 400; manufactured by Cabot) 18 parts by weight and pigment dispersant 2 parts by weight were primarily dispersed in 80 parts by weight of ethyl acetate using a mixer having stirring blades.
As the pigment dispersant, Ajisper PB821 (manufactured by Ajinomoto Fine Techno Co., Ltd.) was used. 100 parts by weight of a polyester resin varnish (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000, ethyl acetate solution solid content 20%) is mixed with the obtained primary dispersion, and strong shearing is performed using a dyno mill. A secondary dispersion was prepared by finely dispersing by force and completely removing aggregates. Furthermore, a 20% solid content liquid was prepared by passing through a filter (manufactured by PTFE) having pores of 0.5 μm and dispersing to a submicron region.

(Preparation of wax dispersion A)
Next, a dispersion liquid having the following composition to which a resin as a binder resin and a wax were added was prepared.
300 parts by weight of a polyester resin (DIC Prototype Polyester Tg: 54.9 ° C., volume average molecular weight 34000), 90 parts by weight of paraffin wax (HPE-11), 10 parts by weight of maleic acid-modified paraffin wax (P-166), As in the preparation of the colorant dispersion, 600 parts by weight of ethyl acetate was stirred for 10 minutes using a mixer having stirring blades, dispersed, and then dispersed for 8 hours using a dyno mill.
As a result of analyzing an electron microscope photograph of the dispersion with image processing software, the dispersed wax has a long side 50% diameter of 2.8 μm, a 90% diameter of 4.5 μm, and a short side of 50% diameter. 0.1 μm, 90% diameter was 0.2 μm, and average aspect ratio was 24.

(Preparation of wax dispersion B)
Next, a dispersion liquid having the following composition to which a resin as a binder resin and a wax were added was prepared.
300 parts by weight of a polyester resin (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000), 80 parts by weight of paraffin wax (HPE-11), 20 parts by weight of maleic acid-modified paraffin wax (P-166), As in the preparation of the colorant dispersion, 600 parts by weight of ethyl acetate was stirred for 10 minutes using a mixer having stirring blades, dispersed, and then dispersed for 8 hours using a dyno mill. Next, a dispersion liquid having the following composition to which a resin as a binder resin and a wax were added was prepared.
As a result of analyzing an electron microscope photograph of the dispersion with image processing software, the dispersed wax has a 50% diameter of 2.2 μm, a 90% diameter of 3.2 μm, and a 50% diameter of the short side. 0.3 μm, 90% diameter was 0.4 μm, and average aspect ratio was 7.

(Preparation of wax dispersion C)
Disperse the colorant in 300 parts by weight of polyester resin (manufactured by DIC, prototype polyester Tg: 54.9 ° C., volume average molecular weight 34000) and 100 parts by weight of ester wax (prototype 44, Nippon Oil & Fats) in 600 parts by weight of ethyl acetate As with the liquid preparation, the mixture was stirred for 10 minutes using a mixer having stirring blades, dispersed, and then dispersed for 8 hours using a dyno mill.
As a result of analyzing an electron microscope photograph of the dispersion with image processing software, the dispersed wax has a long side 50% diameter of 1.8 μm, a 90% diameter of 2.5 μm, and a short side of 50% diameter. 0.3 μm, 90% diameter was 0.4 μm, and average aspect ratio was 6.

(Preparation of wax dispersion D)
Next, a dispersion liquid having the following composition to which a resin as a binder resin and a wax were added was prepared.
300 parts by weight of polyester resin (manufactured by DIC, prototype polyester Tg: 54.9 ° C., volume average molecular weight 34000), 100 parts by weight of paraffin wax (HPE-11), 600 parts by weight of ethyl acetate, and at the time of preparing the colorant dispersion Similarly, after stirring and dispersing for 10 minutes using a mixer having stirring blades, dispersion was performed for 8 hours using a dyno mill.
As a result of analyzing an electron microscope photograph of the dispersion with image processing software, the dispersed wax has a long side 50% diameter of 1.8 μm, a 90% diameter of 2.5 μm, and a short side of 50% diameter. 0.4 μm, 90% diameter was 0.5 μm, and average aspect ratio was 5.

(Preparation of wax dispersion E)
Next, a dispersion liquid having the following composition to which a resin as a binder resin and a wax were added was prepared.
200 parts by weight of a polyester resin (manufactured by DIC, prototype Tg: 54.9 ° C., volume average molecular weight 34000), 100 parts by weight of a styrene resin RSWD-A (manufactured by Sanyo Kasei), 100 parts by weight of carnauba wax (WA-05) As in the preparation of the colorant dispersion, 600 parts by weight of ethyl acetate were stirred for 10 minutes using a mixer having stirring blades, and then dispersed for 8 hours using a dyno mill. .
As a result of analyzing an electron microscope photograph of the dispersion with image processing software, the dispersed wax has a 50% diameter of 1.2 μm on the long side, a 2.0% diameter on the 90% side, and a 50% diameter on the short side. The diameter was 0.2 μm, the 90% diameter was 0.3 μm, and the average aspect ratio was 6.

(Preparation of wax dispersion F)
Next, a dispersion liquid having the following composition to which a resin as a binder resin and a wax were added was prepared.
300 parts by weight of polyester resin (manufactured by DIC, polyester Tg: 54.9 ° C., volume average molecular weight 34000), 70 parts by weight of paraffin wax (HPE-11), 30 parts by weight of maleic acid-modified paraffin wax (P-166), As in the preparation of the colorant dispersion, 600 parts by weight of ethyl acetate was stirred for 10 minutes using a mixer having stirring blades, dispersed, and then dispersed for 8 hours using a dyno mill.
As a result of analyzing an electron microscope photograph of the dispersion with image processing software, the dispersed wax has a long side 50% diameter of 1.8 μm, a 90% diameter of 2.5 μm, and a short side of 50% diameter. 0.4 μm, 90% diameter was 0.6 μm, and average aspect ratio was 6.

(Preparation of wax dispersion G)
Next, a dispersion liquid having the following composition to which a resin as a binder resin and a wax were added was prepared.
300 parts by weight of a polyester resin (DIC Prototype Polyester Tg: 54.9 ° C., volume average molecular weight 34000), 90 parts by weight of paraffin wax (HPE-11), 10 parts by weight of maleic acid-modified paraffin wax (P-166), Similarly to the preparation of the colorant dispersion, 600 parts by weight of ethyl acetate was stirred for 10 minutes using a mixer having stirring blades, dispersed, and then dispersed for 2 hours using a dyno mill.
As a result of analyzing an electron microscope photograph of the dispersion with image processing software, the dispersed wax has a 50% diameter of 3.5 μm in the long side, 6.2 μm in the 90% diameter, and a 50% diameter in the short side. The diameter was 0.3 μm, the 90% diameter was 0.4 μm, and the average aspect ratio was 14.

<Preparation of Toner Composition Liquid A>
25 parts by weight of a colorant dispersion, 50 parts by weight of wax dispersion A, 75 parts by weight of a polyester resin (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000) and 850 parts by weight of ethyl acetate are mixed with a homomixer. A toner composition A having a solid content of 10% was prepared by stirring.

<Preparation of toner composition liquid B>
Mixing 25 parts by weight of the colorant dispersion, 100 parts by weight of the wax dispersion B, 55 parts by weight of a polyester resin (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000) and 820 parts by weight of ethyl acetate are mixed with a homomixer. A toner composition liquid B having a solid content of 10% was prepared by stirring.

<Preparation of toner composition liquid C>
25 parts by weight of a colorant dispersion, 100 parts by weight of a wax dispersion C, 55 parts by weight of a polyester resin (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000) and 820 parts by weight of ethyl acetate are mixed with a homomixer. A toner composition liquid C having a solid content of 10% was prepared by stirring.

<Preparation of toner composition liquid D>
Mix 25 parts by weight of the colorant dispersion, 70 parts by weight of the wax dispersion D, 67 parts by weight of a polyester resin (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000), and 838 parts by weight of ethyl acetate. A toner composition liquid D having a solid content of 10% was prepared by stirring.

<Preparation of toner composition liquid E>
Mixing 25 parts by weight of the colorant dispersion, 100 parts by weight of the wax dispersion E, 55 parts by weight of a polyester resin (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000), and 820 parts by weight of ethyl acetate. A toner composition E having a solid content of 10% was prepared by stirring.

<Preparation of toner composition liquid F>
Mixing 25 parts by weight of the colorant dispersion, 150 parts by weight of the wax dispersion F, 45 parts by weight of a polyester resin (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000), and 780 parts by weight of ethyl acetate, using a homomixer A toner composition liquid F having a solid content of 10% was prepared by stirring.

<Preparation of Toner Composition Liquid G>
Mix 25 parts by weight of the colorant dispersion, 70 parts by weight of the wax dispersion D, 67 parts by weight of a polyester resin (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000), and 838 parts by weight of ethyl acetate. A toner composition liquid G having a solid content of 10% was prepared by stirring.

<Preparation of toner composition liquid H>
25 parts by weight of a colorant dispersion, 95 parts by weight of a polyester resin (prototype polyester Tg manufactured by DIC: 54.9 ° C., volume average molecular weight 34000) and 880 parts by weight of ethyl acetate are mixed, stirred with a homomixer, and 10% solids toner Composition liquid H was prepared.

(Create toner base)
The obtained toner composition-containing liquids A to H are spray-dried using the electrophotographic toner manufacturing apparatus shown in FIG. 1, and toner bases A to H, A ′ to H ′, and A ′ as shown in Table 1 are used. I got '~ H'.
[Production of toner bases A to H]
The toner composition liquid is quantitatively supplied to the storage unit of the toner manufacturing apparatus shown in FIG. 22 and the toner composition-containing liquid is stored while being excited by the vibration means in contact with a part of the storage unit. The toner composition-containing liquid is discharged into the granulation space from a plurality of through-holes provided in the section, and the toner composition-containing liquid is converted into droplets from a columnar shape through a constricted state, and the droplets are turned into solid particles in the granulation space The toner bases A to H were prepared by spray drying using a spraying means using a vibrating chamber nozzle head to be changed and then drying at a reduced rate in a 50 ° C. atmosphere in a fluidized bed dryer.

[Production of toner bases A ′ to H ′]
A toner base was manufactured using the toner manufacturing apparatus shown in FIG. 1 instead of the spraying means using the chamber nozzle head. That is, the thin film having a plurality of nozzles provided in the reservoir for storing the toner composition-containing liquid is vibrated by a mechanical vibration means (horn-type vibrator) to periodically discharge the toner composition liquid from the thin film nozzles. The toner bases A ′ to H ′ are spray-dried using a spraying means using a liquid ejecting unit (see FIG. 2) that discharges into droplets, and is then reduced in a fluidized bed dryer in an atmosphere at 50 ° C. It was created.
The used nozzle plate was produced by electroforming a perfect circular discharge hole having a diameter of 8 μm on a nickel plate having an outer diameter of 8.0 mm and a thickness of 20 μm. The discharge holes were provided in a staggered pattern so that the distance between the discharge holes was 100 μm, and only in the range of about 5 mmφ at the center of the nozzle plate. In this case, the number of effective discharge holes in calculation is 1000.
After the dispersion was prepared, the droplets were discharged under the following toner production conditions, and then the droplets were dried and solidified to produce toner base particles.
(Jet drying conditions)
Dry air flow rate: Dispersing nitrogen gas 2.0 L / min,
Dry nitrogen gas in the device 30.0 L / min Temperature in the device: 38 to 40 ° C
Nozzle frequency: 180 kHz
Piezoelectric applied voltage: 10V

[Production of toner bases A "to H"]
After spray drying using the toner production apparatus of FIG. 11 equipped with a ring-type droplet jetting unit using an annular vibration generating means shown in FIG. 12, it is reduced in a 50 ° C. atmosphere in a fluidized bed dryer. Thus, toner bases A ″ to H ″ were prepared.
The nozzle plate and spray drying conditions were the same as described above.

The production stability of the toner was evaluated when the toner base was prepared. In order to obtain 1.0 kg of toner base particles, the flow stability of the nozzle head when 10 kg of toner material liquid is continuously sprayed is evaluated by the flow rate after discharge of 10 kg / initial flow rate. Less than 99% was evaluated as x when stability was not obtained.
The obtained toner base was observed with a TEM cross section, the state of the release agent inside the toner was observed, and the long side of the release agent / toner particle size was calculated.

(Create toner)
The toner bases having the same symbols of the toner bases A to H, A ′ to H ′, and A ″ to H ″ using the ejection units basically have the same characteristics because they have the same material configuration and the same state. Hereinafter, an example in which toner is prepared by mixing external additives with respect to toner base toner bases A to H will be evaluated.
Toners A to H were obtained by mixing 1.5 parts by weight of H1303 (hydrophobized silica) and 0.8 parts by weight of MA150AI (hydrophobized titania) with a Henschel mixer with respect to 100 parts by weight of toner bases A to H. The external additives were mixed for imparting fluidity and adjusting charging characteristics.
FIG. 28A is a TEM cross-sectional photograph of the toner of Example (left: Example 1, right: Example 2).
FIG. 28B is a TEM cross-sectional photograph of a comparative example (upper left: comparative example 3, upper right: comparative example 4, lower left: comparative example 5, lower right: comparative example 1).
FIG. 28C is a diagram showing a dispersed state of wax having an aspect ratio within the range of the present invention.
FIG. 28D is a diagram showing a dispersion state of wax having a small aspect ratio.

(Create developer)
The toner of the present invention is not limited to either a one-component developer or a two-component developer, but in this embodiment, the following carrier and toner: carrier are mixed so that the ratio is 7:93. Evaluation was performed as H.
(Career)
Core material: Spherical ferrite particles with an average particle size of 35 microns Coating material: Mixture of silicone resin and melamine resin

The following evaluation was performed by a tandem color electrophotographic apparatus (“Imagio Neo C350”; manufactured by Ricoh Co., Ltd.).
The developer is put into the developing unit of the apparatus (first AD, second EG), and 10,000 sheets are run using 6000 paper manufactured by Ricoh with an image occupancy ratio of 5%. Dirt was evaluated.
The ID value variation of the non-image portion was less than 0.03, and 0.03 or more was rejected.

(Fixation evaluation)
In the above apparatus, the apparatus was adjusted so that a solid image with a toner adhesion amount of 0.8 mg / cm 2 was obtained, and the fixing temperature range was sequentially increased from 130 ° C. every 10 ° C. to measure the fixing temperature range (first time A to A). D, 2nd EH). At this time, adjustment was made so that the solid images of the respective toners do not overlap each other, and the fixing temperature range was defined as the upper limit temperature at which the gloss value of the obtained image was lower than the previous temperature condition.
The fixing temperature of Developer H that does not use a release agent was determined to be acceptable at + 30 ° C. and rejected at less than + 30 ° C. In addition, a sample that generated a cold offset at 130 ° C. fixability was also rejected.

  From the above, it is apparent that the present invention is a toner having a stable continuous sprayability and a stable fixing property in the toner sprayed from the nozzle. Further, the toner production method of the present invention makes it possible to produce a monodispersed toner having stable fixing properties.

   The toner of the present invention is excellent in monodispersibility and satisfies high image quality, fixability, and high productivity, and therefore can be suitably used as an electrophotographic toner.

FIG. 3 is a schematic configuration diagram illustrating an example of a toner manufacturing apparatus according to the present invention. FIG. 6 is an enlarged explanatory diagram for explaining a droplet ejecting unit of the toner manufacturing apparatus. It is bottom explanatory drawing which looked at FIG. 2 from the lower side. It is a typical explanatory view showing an example of a step type horn type vibrator constituting the vibration generating means of the liquid droplet ejecting unit. It is a typical explanatory view showing an example of an exponential horn type vibrator constituting the vibration generating means of the liquid droplet ejecting unit. It is a typical explanatory view showing an example of a conical horn type vibrator constituting the vibration generating means of the liquid droplet ejecting unit. FIG. 6 is an enlarged explanatory diagram for explaining another example of the droplet ejecting unit of the toner manufacturing apparatus. FIG. 10 is an enlarged explanatory view for explaining still another example of the droplet ejecting unit of the toner manufacturing apparatus. FIG. 10 is an enlarged explanatory view for explaining still another example of the droplet ejecting unit of the toner manufacturing apparatus. FIG. 10 is an explanatory diagram for explaining an example in which a plurality of droplet ejecting units of FIG. 9 are arranged. 1 is a schematic configuration diagram illustrating an embodiment of a toner manufacturing apparatus according to the present invention. FIG. 6 is an enlarged explanatory diagram for explaining a droplet ejecting unit of the toner manufacturing apparatus. It is bottom face explanatory drawing which looked at FIG. 13 from the lower side. It is expansion sectional explanatory drawing of the droplet formation means of the droplet ejection unit. It is expansion sectional explanatory drawing of the droplet formation means which concerns on a comparative example structure. FIG. 3 is a main part explanatory diagram for explaining a specific application of the toner manufacturing apparatus. It is a typical explanatory view of a thin film used for explanation of an operation principle of droplet formation by the droplet ejection unit. It is explanatory drawing similarly used for description of a fundamental vibration mode. It is explanatory drawing similarly used for description of secondary vibration mode. It is explanatory drawing similarly used for description of a tertiary vibration mode. It is explanatory drawing at the time of forming a convex part in the center part of a thin film similarly. It is explanatory drawing of an example of the toner particle manufacturing apparatus for implementing this invention. It is explanatory drawing of an example of the storage part of the toner manufacturing apparatus in this invention. It is a figure which shows an example of an internal structure of a color image forming apparatus. It is a figure which shows an example of an internal block diagram of a developing device. It is a figure which shows an example of an internal block diagram of a developing device. It is a figure which shows schematic structure of a process cartridge. 3 is an example of a toner cross-sectional photograph of an example relating to a toner according to the present invention. 4 is an example of a toner cross-sectional photograph of a comparative example related to the toner according to the present invention. It is a figure which shows the dispersion state of the wax whose aspect ratio is the category of this invention. It is a figure which shows the dispersion state of the wax with a small aspect ratio.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Toner manufacturing apparatus 2 Droplet jet unit 3 Particle formation part (solvent removal part)
DESCRIPTION OF SYMBOLS 4 Toner collection part 5 Tube 6 Toner storage container 7 Raw material storage part 8 Piping 9 Pump 10 Toner composition liquid 11 Nozzle 12 Thin film 13 Vibrating means 13a Vibrating surface 14 Reserving part 15 Flow path member 16 Droplet forming means 17 Vibration generating means ( Electromechanical conversion means)
18 liquid supply tube 19 bubble discharge tube 20 support member 21 vibration generating means 21A piezoelectric body 22 vibration amplifying means 22A horn 23 drive circuit (drive signal generation source)
24 communication means 31 droplet 35 air flow 36 air flow path forming member 37 air flow path 80 horn type vibrator 81 piezoelectric body 82 horn 83 fixing portion 90 Langevin type vibrator 91 piezoelectric body 92 horn T toner particle

Claims (13)

  Electrons manufactured by forming a droplet by discharging a toner composition liquid in which at least a resin, a release agent, and a colorant are dissolved or dispersed in an organic solvent from a plurality of nozzles, and solidifying the droplet. A photographic toner, wherein the resin is soluble in the organic solvent, and the release agent has a 90% short side diameter of 100 to 500 nm, an average aspect ratio of 7 to 30 and a long side in the toner. Is dispersed in a state of particles having a length of ½ or more and less than 1 of the particle diameter of the toner.   The electrophotographic toner according to claim 1, wherein the releasing agent has a melting temperature of 50 to 100 ° C.   The toner for electrophotography according to claim 1 or 2, wherein the content of the release agent in the toner is 3 to 20 wt%.   The toner for electrophotography according to any one of claims 1 to 3, wherein the volume average particle diameter is 3.0 to 7.0 µm.   5. The electrophotographic toner according to claim 1, wherein the ejection is performed while vibrating the reservoir from a plurality of nozzles provided in the reservoir that stores the toner composition liquid. 6.   The electrophotographic toner according to claim 5, wherein the nozzle is a vibration chamber nozzle head.   In the ejection, the toner composition liquid is periodically discharged from the nozzles of the thin film by vibrating a thin film having a plurality of nozzles provided in a storage portion for storing the toner composition liquid by mechanical vibration means. The toner for electrophotography according to claim 1, wherein the toner is an electrophotographic toner.   8. The electrophotographic toner according to claim 7, wherein the mechanical vibration means is vibration generation means formed in an annular shape around a region where the thin film nozzle is provided.   8. The electrophotographic toner according to claim 7, wherein the mechanical vibration means is a vibration means having a vibration surface parallel to the thin film, and the vibration surface vibrates in the vertical direction.   The electrophotographic toner according to claim 9, wherein the vibration unit is a horn-type vibrator.   The electrophotographic toner according to any one of claims 7 to 10, wherein the vibration frequency of the mechanical vibration means is 20 kHz or more and less than 2.0 MHz.   An electrophotographic image forming apparatus using the electrophotographic toner according to claim 1.   An electrophotographic process cartridge using the electrophotographic toner according to claim 1.